Shizuoka residents back Hamaoka nuclear restart for fourth straight year
Surveys in host municipalities show support for restart outpacing opposition four years running, removing a key local barrier as Japan targets 20% nuclear power by 2040.
Residents of Kakegawa City in Shizuoka Prefecture have backed restarting the Hamaoka nuclear power plant over keeping it suspended or decommissioning it for the fourth consecutive year, a survey by the Shizuoka Shimbun showed. Adjacent Kikugawa City returned the same result. In Japan, sustained host-community opposition has historically been sufficient to block reactor restarts even where regulatory approvals existed; four consecutive years of majority support represents a meaningful change in that constraint.
Japan's government is targeting nuclear power at roughly 20% of electricity generation by fiscal 2040, compared with 9.4% in fiscal 2024.2 The industry ministry has drafted plans for two to five new reactors to be built by the 2040s, with potentially 14 replacement units approved by 2050.2
Officials estimate the country will need between 2.2 million and 5.5 million kilowatts of replacement capacity to avoid supply shortfalls as ageing plants retire, pressure that becomes acute after 2040.2 Restarting an already-built plant preserves megawatts Japan would otherwise have to replace with new capacity, making it a faster route toward the 20% target than construction.
Before the 2011 Fukushima accident, Japan operated 54 reactors supplying around 25% of its electricity, with a government ambition to expand nuclear to 50% by 2030.1 That ambition dissolved after the disaster. The current 20% target reflects a more cautious recovery, contingent on maintaining existing approved reactors and clearing suspended plants through regulatory review.1
Japan's energy plan also projects renewables at between 40% and 50% of the mix by 2040, up from roughly 25% in recent years.1 Researchers at the Lawrence Berkeley National Laboratory have estimated that renewables could reliably supply as much as 70% of Japan's electricity by 2035 — well above the government's own target — though the projection depends on grid upgrades and storage capacity that have not yet been built.1 The gap between the academic estimate and official policy reflects genuine uncertainty about the pace and ambition of Japan's non-nuclear transition.
The operating picture elsewhere in Japan's nuclear fleet has been mixed. KEPCO has indicated its nuclear capacity utilisation rate will fall to 70.5% in FY2026, down 10.4 percentage points year-on-year, because of extended inspections and steam generator replacement work across multiple units at the Takahama plant.3 Even approved and operational reactors can drag on output when maintenance runs long — a reminder that utilisation, not just approved capacity, is the binding variable in meeting Japan's electricity targets.
Community sentiment at Hamaoka does not accelerate the regulatory clock. Japan's nuclear regulator and national government clearance are both required before the plant can restart, and neither condition has been met. Local support is a political prerequisite; the regulatory review sets its own timeline independently.
Still, the four-year survey trend carries weight. Local opposition in Japan has derailed restart processes even after central government and regulator sign-offs were in place; a sustained majority in Kakegawa and Kikugawa removes that potential veto. Whether the plant's operator translates this signal into a formal restart application — and whether regulatory milestones can support that timeline — will determine how soon Hamaoka can contribute to a nuclear mix that currently sits more than 10 percentage points below the government's 2040 target.2